Maturing of crops



Patented Aug. 18, 1953 MATURING OF CROPS Richard N. Raynor, Danville,and Doane Stewart, Garden Grove, Calili, assignors. to The Dow ChemicalCompany, Midland, Mich., a corporation of Delaware No Drawing;Application November 29, 1951, Serial No. 258,994

4 Claims. 1.

This invention relates to the maturing of crops and is particularlydirected to. a method for facilitating the harvest. of field crops.

Among the problems. peculiar to largeiscale agricultural operations is;the promotion of early and uniform ripening of the fruitsorothergcommercial products of field crops to permit an orderly andeconomical harvest. This is. particularly the casewhere mechanical.harvesting means have been devised andarein. general usage as withcotton. Here the presence of a substantial amount of immature orpartially. developed bolls materially reduces the yield per acre, andnullifies the economic advantages otherwise attendant uponthe-mechanical picking operation. Also, the presence of a heavy set ofgrowing leaves on cotton plants notonly interferes with the actualpicking operation, butv results in. an excess of trash in the pickedfibers which isseparated only with difiiculty.

Somewhat similar problems: are encountered with respect to themechanicalharvestof beans and potatoes, and particularly under climatic conditionswhere-frosts cannot be depended upon to kill the vines, thus permittingthe latter to continue growth in spite of: the presence of ma.- tureseed pods and tubers. Withbeans, following a conventional sub-surfacecut-ting operation or the pulling of the vines, it' isalsonecessary torake, windrow and turn the. cropin order that the vines and pods maybedry enough to thresh. I

Not only is this time-consuming and expensive as to labor costs, butalso theloss of beans due to shattering of the podsis considerable.

With potatoes, the continuing growth of the vines; even after the tubershave reached optimum size, constitutes a tremendous obstacle tomechanical digging operations. The lush and succulent growing plantblocksthe actionof. the moving parts of conventional digging apparatussometimes leading to breakdowns, and. at. best necessitating frequentstops toclearthe tangled vines from gear and belt assemblies. Also/thecontinued growth of vines, particularly during the rainy season,provides-'anaeasy point ofattack for blight and virus organisms which.are .translocated to the mature tubers, thus. eliminating, thepossibility of'their subsequent. use, as-seed and-ma.- terialiyreducingv their keeping; qualities and market value. Further, with.-.an;unnecessarily prolonged growing season, for the: vines it is difiicultto accomplish the hardening; off of the po tatoes. Wherethevinesarevkilled or otherwise materially reduced invieorbynaturalcauses, the potatoes, may be left in;the soi for ashort period duringwhich the skin forms a corky layer of determinable thicknesswhichprotects the body of the tuber from abrasion and bruising in thedigging, cleaning and marketing operations. This hardening does not:take place while the tuber continues to grow andreceive nourishment fromthe vines; Thus the digging of the tubers prior to the destruction of.the vines. and subsequent resting interval in the soil to permithardening oh, results in a thin-skinned potato much more liable toinjury than would otherwise be the case.

Other crops presenting problems as regards maturing and harvesting, arepeppers and tomatoes. While these crops are not generally harvested bymechanical means, their normal growth habits are such that but a fewfruit mature at one time so that a given planting must be hand pickedmany times, if a maximum yield is to be obtained. Also, bothpeppers andtomatoes put forth a very rank growth of leaves and stalks, so that, inthe average planting, it is almost impossible to ascertain the locationof early ripening fruits without so breaking down the vines as seriouslyto interfere with the maturing of the green fruits. Further; the densefoliage shades the immature fruits so as to retardthe ripening process.

tis an object of the present invention to proide means for hastening thematuring of crops. A further object is to'provide a method for promotingthe uniform development and ripening of field crops to facilitate theirharvest. An additional object is toprovide means for the defoliation offield crops and particularly cotton.- Other objects will'become evidentfrom the following specification and claims.

According to-the-present invention,,it has been discovered that many ofthe. foregoing problems are solved and the objects of the inventionachieved if field crops are treated at a time near the end of theirnormal growing season with a Water-soluble halopropionic acid compoundof the 7 group having the a formula (XR J-O) ..-W'

wherein XR.- represents a monohaloethyl radical, X represents-.a.halogenof the. group. consisting of chlorine, vbromineandiodine, W representsone of thegroupconsisting of hydrogen and a salt forming. ion,,and nrepresents an integer equal to the equivalency of W. This treatmentaccomplishes the promotion of thematuring of the crops, and an earlyanduniform ripening of the fruit... or other. commercial. product so as tofacilitate harvest. In manyinstances, the operation accomplishes atleast partial" defoliation been found particularly advantageous. Thehaloh acid compounds on contact with the plant surfaces causedefoliation at dosages that do not kill the leaf blade, thusfacilitating mechanical picking operations and minimizing leaftrash inthe picked cotton. This defoliation action is accom'- plished on rankgreen plants as well as dry mature plants, and accelerates the rate ofopening of otherwise closed bolls so as to permit the gathdispersed inwater in the desired concentration. Similarly, the effective ingredientmay be dissolved or dispersed in light petroleum distillate or inoil-water emulsions. In either event, suitable wetting, dispersing oremulsifying agents may be employed if desired. Operable additameritsinclude polyhydric esters of fatty acids (Emcol CA), ethyleneoxidecondensate with fatty acids (Emulphor AG), polyethylene glycol coneringof a high percentage of the fiber in a single picking operation. Stemtissue and immature bolls are not significantly injured at the effectivedefoliant dosage, and the bolls quickly mature following the abscissionof any appreciable portion of the foliage. The effective compounds arewater-soluble, but do not depend on dew, rain, or high atmospherichumidity to accomplish defoliant action. Aqueous solutions ondispersions of the haloacid compounds do not stain the lint of openedbolls or weaken the cotton fibers.

On peppers, the method accomplishes a partial kill of leaves andsufficient defoliation without stalk injury to open up the plant tosunlight. Whether as a result of physiological responses in the plant orthe increased light intensity, immature peppers show a rapiddevelopment. The combination of results ermits of a convenient andeconomical manual picking of the fruit with a high percentage of thecommercial crop harvested in a single pass through the field. Thetreatment does not injure the fruit at the dosage required-for leafthinning, nor impart any undesirable taste or odor characteristicsthereto.

A similar'result is obtained in the treatment of tomatoes. Here, theleaves become dry and shrunken but without appreciable defoliation. 'Ihestalks, fruit and fruit stems do not appear to be materially affected atthe necessary dosages so that there is little fruit fall but a definitespeeding up of the ripening process. With the reduction in leaf surface,early ripening fruit can be observed and spot picked for early market,and the bulk of the crop gathered in a single picking operation.

On potatoes, with adequate dosage, the vines undergo a quick kill,whereby the tubers stop growth and harden off in the soil. The vinesquickly shrivel and desiccate and offer no problem in mechanical diggingoperations. There appears to be no translocation of the haloacidcompound through the vines to the tubers, so that the eating qualitiesof the potatoes are not affected.

Vfhen operating in accordance with the present invention, the effectivehaloacid compound may be employed as a constituent of either sprays ordusts as may be convenient. In such form the compositions may be appliedeither manually with small spray equipment such as knapsack sprayers orwith any suitable hand duster. Preferred operation includes applicationfrom the ground with mechanized spray or dust equipment or from the airby plane. In either of the latter situations uniform distribution of thecomposition and thorough coverage of plant surfaces are con ducive ofoptimum results.

When sprays are to be employed, the haloacid compound may simply bedissolved or otherwise vines or stalks of the crop.

densate (Emulphor D), polyalkylene ether alcohol (Triton),polyoxyalkylene derivative sorbitan monolaurate' j(Tween 20),polyoxyalkylene derivative of sorbitan trioleate (Tween sodium laurylsulphate, and alkali metal salts of sulfonated aromatic hydrocarbons andphenols. Suitable dust carriers include diatomaceous earth, volcanicash, talc, pyrophyllite, finely divided clays, ypsum, and wood flour.

In practicing the invention, best results are obtained when the spray ordust mixtures are so applied as to obtain uniform distribution over theleaf surfaces of the plants under treatment. Also, application should bemade at a time when the fruits or other desired plant product approachmaturity and near the end of the normal growing season of the crop.Application is preferably made when the air temperature is 60 F. orhigher, or when temperatures in this range are anticipated shortly afterapplication.

lhe dosages of haloacid compound employed vary considerably with theparticular crop under treatment, the result desired, the climaticconditions at time of application, and the nature and form of thecomposition employed. In general, from about. 10 to 50 pounds per acrehave been found to give the best results. Dosages in the lower portionof this range are productive of good results in spray compositions.Somewhat larger dosages are recommended where a dust composition isbeing employed. In many instances it is best to avoid the application ofan excess of haloacid compound lest a complete kill and destruction ofthe plant and crop be obtained instead of the desired hastening ofmaturity. Thus with cotton, the dosage should be so regulated as toobtain from about 40 to per cent defoliation in order to open up theplant. Here any appreciable excess of the active agent may injure theunopened bolls and burn and kill the stems and stalks so as tocomplicate rather than facilitate the harvest. Similarly, with tomatoesand peppers where a defoliation and/or kill of 30 to '75 percent isgenerally adequate and a dosage calculated to give a greater responsemay contribute to the scald of the fruit. With potatoes, peas, beans,flax, milo and the like the concentration is not critical since it isdesired principally to encourage a quick and complete maturing of theSugar cane, when treated to dry back excess leafy vegetation and permiteasy cutting and handling, can be subjected to relatively high dosageswithout material injury to the cane.

The concentration of the haloacid compound in the spray or dustcompositions is not critical so long as uniform distribution isobtained. Generally from about 5 to 50 pounds of active agent pergallons of spray gives best results, again depending upon the particularcrop under treatment. The volume of spray applied may vary from aslittle as 3 or 4 gallons to several hundred gallons per acre. Here thetype of equipment employed is largely controlling.

With dusts, concentrations of from about 1 to 20 percent by weight inthe inert carrier is operable depending upon the conditions of theparticular application. The poundage of dust compositions employed isnot critical so long as the required dosage of active ingredient isthereby distributed in contact with the plant surfaces.

The following examples illustrate the invention but are not to beconstrued as limiting.

Example 1 A number of halopropionic acids were employed in simpleaqueous sprays, without a wetting agent to determine their comparativedefoliating properties on medium staple cotton of the Acala variety. Thestand was somewhat irregular varying from 2 to 5 feet in height andaveraging 3 feet with rows on 40-inch centers. The plants were nearlymature with dense foliage, upper bolls approaching two-thirds of theirultimate size, and some lower bolls open. The soil was dry at time oftreatment, the last irrigation having been 3 weeks previous. The weatherduring both the applications and interim of illspection was warm and drywith temperatures of 60-85 F. The applications were made with a powersprayer at 65 pounds per square inch, employing a high clearance 6-footboom which permitted the coverage of 2 rows in a single application. Thespray volume in each case was 30 gallons per acre, with the spraydroplets penetrating down through the foliage.

The treated plots were inspected one week following treatment todetermine the percentage defoliation. The following table sets forth thedata obtained:

Percent Defoliation Lbs. per

Compound Acre In subsequent inspections, much higher percentages ofdefoliation were observed in all treated plots, with many more bollsopening and a much higher degree of maturity in these plots than wasobserved in the check plot.

Example 2 In a similar fashion, B-chloropropionic acid andB-bromopropionic acid and their potassium and sodium salts are dissolvedin water and employed as sprays for application to the tops of the vinesof a stand of white navy beans approaching maturity. The spray solutionsare applied to a portion of the stand with conventional equipmentoperating at 40 pounds pressure per square inch and at a spray volume of100 gallons per acre. The vines wet readily with little run off. Theforegoing compounds at dosages of from 10 to 50 pounds per acreaccomplish a substantial dry-back of the vines and killing of the leaveswithin a three to four day period. Check areas continue to grow inthrifty fashion. Both treated and check areas are then harvested inconventional manner by subsurface cutting operation. The bean plantsfrom the treated plots quickly dry and are in condition for fieldcombining within a few days. In the untreated check plots,

6 the dry-back of the vines is irregular and windrowing and turningoperations are required for a number of days prior to threshing.

The present application is a continuation-inpart of application SerialNo. 107,393, filed July 28, 1949.

We claim:

1. A method for promoting the maturing of crops and facilitating ofharvest which includes the step of applying to the crops near the end oftheir normal growing season a water-soluble compound of the group havingthe formula wherein XR is a monohaloethyl radical, X represents ahalogen of the group consisting of chlorine, bromine and iodine, Wrepresents one of the group consisting of hydrogen and a saltformingion, and n represents an integer equal to the equivalency of W, suchcompound being employed at a dosage suflieient substantially toaccelerate the maturing of the crops.

2. A method for defoliating field crops to promote the maturing of thecrops and facilitate their harvest which includes the step of applyingto the crops near the end of their normal growing season a water-solublecompound of the group having the formula wherein XR-- is a monohaloethylradical, X represents a halogen of the group consisting of chlorine,bromine and iodine, W represents one of the group consisting of hydrogenand a saltforming ion, and n represents an integer equal to theequivalency of W, such compound being employed at dosage suincient toaccomplish at least partial defoliation of the field crops.

3. A method for defoliating cotton which includes the step of applyingto the leaf surfaces of the cotton plants near the end of their normalgrowing season a water-soluble compound of the group having the formulawherein XR is a monohaloethyl radical, X represents a halogen of thegroup consisting of chlorine, bromine and iodine, W represents one ofthe group consisting of hydrogen and a saltforming ion, and n representsan integer equal to the equivalency of W, such compound being employedat a dosage sufficient to accomplish at least partial defoliation of thecotton plants.

4. A method for defoliating cotton which includes the step of applyingto the leaf surfaces of the cotton plants near the end of their normalgrowing season an aqueous solution of a compound of the group having theformula wherein XR is a monohaloethyl radical, X represents a halogen ofthe group consisting of chlorine, bromine and iodine, W represents oneof the group consisting of hydrogen and a saltforming ion, and nrepresents an integer equal to the equivalency of W, such compound beingemployed at a dosage sufiicient to accomplish at least partialdefoliation of the cotton plants.

RICHARD N. RAYNOR.

DOANE STEWART.

No references cited.

1. A METHOD FOR PROMOTING THE MATURING OF CROPS AND FACILITATING OFHARVEST WHICH INCLUDES THE STEP OF APPLYING TO THE CROPS NEAR THE END OFTHEIR NORMAL GROWING SEASON A WATER-SOLUBLE COMPOUND OF THE GROUP HAVINGTHE FORMULA